Oil cooler



May 2, 1933. J AsKlN 1,907,033

OIL COOLER Filed Jan. 17, 1951 2 Sheets-Sheet 2 Jwuentmn Joseph mm,

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J w W Patented May 2, 1933 UNITED STATES PATENT OFFICE JOSEPH ASKIN, OFBUFFALO, NEW YORK, ASSIGNOB TO FEDDERS MANUFACTURING COMPANY, INCBUFFALO, NEW YORK OIL COOLER Application filed January 17, 1931. Serial1T0. 509,452.

This invention relates to an oil cooling system for internal combustionengines and par ticularly for water cooled engines such as are used inmotor vehicles.

In internal combustion engines it is desirableto maintain thetemperature of. the lubricating oil in the -crank case substantiallyconstant about the degree at which it is most eflicient. Due to thevarious atmospheric conditions under which such engines are operated,however, the oil may be cold and inefficient for a considerable timeafter starting, particularly in cold weather, and may in warm weather,become overheated, causing it to break down and to burn. As the water inthe cooling system of an engine rapidly be-' comes heated to a normaltemperature, and is maintained at this temperature by the water coolingradiator, devices have, heretofore, been interposed in the water coolingsystems to exchange heat from the cooling water to the oil and viceversa.

Certain of these devices have comprised. cellular, or other type, coreelements, similar to the conventional vehicle radiator for en ginecooling, and have had the passages in communication with the enginecrank case for passing oil. The core elements have been interposed inthe water cooling system of the engine so that heat might be exchangedbetween the engine oil and the cooling water. Due to the high viscosityof the oil and the pressure placedupon it by the pumps, which have beenutilized to circulate the oil through the core elements, the oil has, insome instances, ruptured the core elements.

The present invention contemplates an improved means for eii'ecting theheat transfer between the engine oil and the cooling water, including aplurality of heavy tubes disposed within a casing, the tubescommunicating with the oil containing crank case and the casing beinginterposed in the circulatory water cooling system. Radiating fins areprovided upon the tubes which serve to maintain them in fixed relationto one another and to the casing. Distributing headers in communicationwith oil inlet and outlet lines are connected to the oil tubes and serveto unify and strengthen the assembly.

These and other objects and advantages will become apparent from thefollowing description of a typical embodiment of the invention,reference being made to the accompanying drawings, wherein Fig. 1 is aside elevation of an internal combustion engine having a water coolingsystem,

and showing an oil cooling system, in accordance with this invention,installed thereon;

Fig. 2 is a central vertical sectional view through the heat transferdevice;

Fig. 3 is a detail sectional view taken along line 33 of Fig. 4;.

Fig. 4 is a rear elevational view of the heat transfer device, portionsthereof being broken away and shown in cross section; and

Fig. 5 is a detail perspective view.

As shown in Fig. 1, the internal combustion engine 10 has a water jacket11 surrounding the cylinders and a conduit 12 connecting an upperportion of the jacket to a water cooling radiator 13. Conduits 14 and 15connect the lower portion of the radiator 13 to a lower portion of thewater jacket so that water may be. circulated from the jacket throughthe radiator in the manner indicated by the arrows. A water pump 16 maybe interposed along the conduit 15 to positively provide for thecirculation of the engine cooling water. Lubricating oil in the enginecrank case 17 may be forced, by an oil pump 18,

through oil lines 19 and 21 to the oil distributing system which maycarry the oil, under pressure if desired, to the bearings and cylinderwalls, from where it returns by gravity to the crank case.

The heat exchange unit 22 comprises a unitary casing section 23 havingwater inlet and outlet nipples 24 and 25 extending from its oppositesides, the inlet nipple being connected to the conduit 14 and the outletnipple 25 being connected to the conduit 15. 'As shown in Fig. 1, theoutlet nipple may be disposed at a higher level than the inlet nipple. Aflanged casing section26 may be fitted onto the open end of the section23 and secured thereto in a water tight manner as by soldering.

Oil inlet and outlet headers 27 and 28 extend through one side of thecasing and may be soldered to the casing along adjacent corners thereof,as shown in Fig. 4. Threaded nipples 29 form a part of the headers,being crimped and soldered or otherwise secured to the open ends of theheaders. The nipples serve to receive fittings 31 which join the oilline 19 to the header 27 and the line 21 to the header 28. A pluralityof juxtaposed oil cooling tubes 32 connect the headers, the ends of thetubes being fitted and secured into flanged openings 33 which are formedin the headers. The tubes are preferably of serpentine form in orderthat they may be of comparatively great length and yet fit within theconfines of the comparatively small easing. As depicted in Fig. 2 thebonds of the tubes may abut, and may if desired be secured to, oppositewalls of the casing.

Heat radiating fins 34 of corrugated or undulated sheet metal may besecured to opposite sides of the straight sections of the cooling tubes.The fins may each comprise a continuous strip as illustrated and mayextend substantially the length of the tube convolutions. Opposite sideedges of the fins may be in abutment, as shown in Figs. 2 and 5, withthe edges of adjacent fins. and the outer fins 34 on each tube may haveportions in abutment with the walls of the casing, thereby preventingrelative movement of the tubes and headers with the casing walls.

In building up the assembly the tubes 32 may be joined to the headers,the fins beingattached to the tubes either before or after thisoperation. The cooling tube and header assembly may then be secured inthe casing section 23, and the flanged casing section 26 may then beapplied, completing the unitary element 22, which may then be installedon the engine. In operation water heated in the jacket 11 of the enginewill be cooled by ciroulating through the radiator 13, and will be drawninwardly through the nipple 24 around the fins 34 and tubes 32, throughthe nipple 25 to the pump 16. Oil may circulate, being pumped underpressure if desired, from the crank case 17 through the line 19 to theheader 27, and through the tubes 32 to the header 28. From the latter itwill be conducted through the line 21 to the oil distributing system ofthe engine.

It will be understood that the oil in passing through the tubes 32 willbe cooled to substantially the temperature of the water passing throughthe casing 23 so that cool and efficient lubricating oil will bedelivered to the engine. Should the engine be operated in cold weatherso that the crank case is unduly cooled, the process of heat transfermay be reversed and the water, heated in the engine jacket, may beutilized to heat the oil. It will further be understood that theheatexchange unit will be efficient in operation due to the large heattransfer surfaces provided by the tubes 32 and fins 34 for contact withthe water. The oil cooling elements may be rigidly supported as a umtaryelement, the fins 34 and tubes 32 being adapted for abutment with thecasing walls and the headers 27 and 28 being joined to the walls. Theheaders and tubes may be assembled as a unit and thereafter inserted inthe casing, adapting the device to simple and economical manufacture.Ample surface of contact is provided for making all connections of theoil passageways, enabling the device to with stand such pressure as maybe imposed upon the oil by an oil circulating pump.

It will still further be understood that the device described andillustrated is merely a typical embodiment of the principles of theinvention and that other devices may be constructed utilizing theseprinciples. It is therefore intended that the invention be considered ofscope commensurate with the appended claims.

What is claimed is:

1. A heat transfer device for exchanging heat between the water of anengine cooling system and the oil of the engine lubricating system,comprising a casing having water inlet and outlet openings at oppositesides thereof, a pair of oil conducting headers extending through a wallof the casing and secured in corners of said casing, a plurality of oiltubes each joined to and in communication with each of said headers,said tubes be ing of serpentine form and comprising bend portionsabutting the walls of the casing and substantially straight portionsconnecting the bend portions, said straight portions being provided-onopposite sides with heat radiating and conducting fins, the fins ofadjacent tubes abutting and the fins of the tube portions adjacent tothe casing walls abutting the latter, and the fins of each tube beingspaced from the otherfins of each tube whereby water passageways areprovided about the tubes and fins between said water inlet and outletopenings.

2. A heat transfer device comprising a casing, a pair of fluidconducting headers disposed within said casing, a plurality of tubesconnecting said headers, each tube being of serpentine form comprisingsubstantially straight portions joined by bend portions, heat radiatingand conducting fins disposed along the straight portions, the fins ofadjacent tubes being in abutment and the fins of each tube being spacedto provide water passages therebetween, and said casing having fluidinlet and outlet openings at sides thereof which are adjacent said bendportions of the tubes.

3. A heat transfer device comprising a casing, a pair of fluidconducting headers secured to the wallsof said casing, a plurality ofsimilar tubes connecting said headers and being arranged therealong intandem, portions of said tubes abutting the walls of said casing forreinforcing the assembly, and said casing having fluid inlet and outletopenings,

whereby fluid may be circulated through the Casing to exchange heat withfluid in said tubes.

4. A heat transfer device comprising a casing having fluid inlet andoutlet openings, a pair of fluid conducting headers secured to saidcasing and a plurality of tubes joined to said headers in tandem andproviding for fluid passage from one to the other of said headers withinsaid casing, and corrugated v fins on each of said tubes abutting thefins of adj acenttubes for reinforcing the device and for providing alarge area of contact between the tubes and fluid Within the casing.

5. A heat transfer device comprising a casing having fluid inlet andoutlet openings, a pair of fluid conducting headers secured to 29 saidcasing and a plurality of tubes joined to said headers in tandem andproviding for fluid passage from one to the other of said headers withinsaid casing, and corrugated fins on each of said tubes abutting the finsof adjacent tubes for reinforcing the device and for providing a largearea of contact between the tubes and fluid Within the casing, thecorrugations of adjacent fins being staggered to provide for positiveabutment of adjacent 6. A heat transfer device comprising a casinghaving fluid inlet and outlet openings, said casing being composed of aplurality of sections, at least one of said sections having openingsformed therein for receiving fluid inlet and outlet headers, a unitcomprising a pair of headers, a plurality of tubes connecting saidheaders, and heat transferring fins on said tubes, the fins on adj acenttubes abutting, and said unit being adapted to be insorted and securedin said casin with portions of the headers extending t rough theopenings provided therefor in the casing.

JOSEPH ASKIN.

